Synchronous timing belts [SRO]

This. ALL matter stretches under gravitational waves. It’s all about “how much” when it comes to “stretch”.

The thing is – when people read that they stretch, they aren’t picturing some microscopic amount, they’re picturing rubber bands, and then they start believing the cheap shitty chinesium hub motor sellers who say “belts are bad”. Of course they’re bad – bad to their bottom-line. But not bad for esk8 transmissions.


Wow Brian. Marvellous.

As for the comment quoted, In my experience cheap chinese hub companies never say anything is bad because they are adept at following trends and as such may have said drive in the pipeline.

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@Brenternet The troll this community needs, but not the one it deserves.


When I say elongate under load I am referring to tiny amounts, local, and not permanent. If one tooth is picking up extra load the belt will stretch a tiny amount locally and distribute some load to the adjacent teeth. Only at that point in time. This is a feature of all redundant structures. Load distribution in a row of fasteners between two pieces of aluminum would all go to the outermost two fasteners if this did not happen. In reality the holes elongate slightly and the load distributes to the other fasteners. The stiffer the two parts bolted together are, the less redistribution you get. A belt is soft, allowing a lot of redistribution. Whether it stretches permanently depends on whether you exceed the yield strength, which is approximately 80% of the breaking strength, hence the 80% cutoff.


Wonderful stuff Norm. Can I call you Norm lol.
A sciencey answer to all my ramblings.
Hes asleep or watching friends re runs

On here I am Norm.

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I encouraged that name. I am deeply insulted that you forgot. Oh how we are discarded when our beauty fades

I have no clue what type of belts came on my CGT, but iv’e never changed them. Iv’e gone almost 3 years(and 3 through batteries mind you) and im still running them to this day.

Adjustment has been the same, they have not stretched.


I rode for 40min with a brand new 12mm belt, cheap AF. It was skipping teeth when I was breaking at the end of my ride. My motor or mount didn’t move at all. So I guess cheap belts are… cheap quality. I’ll keep using that belt for a bit, I’m interested to see if it’ll keep stretching.

Also, would a wider belt stretch less?

I remember. I was just reinforcing that it is official and permanent.

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I know right. I’m still riding on my originals and I ordered an additional set when I purchased the board. Never a skip or anything.

Belts don’t stretch.

A wider belt is much less likely to skip, though.

Is this right though? Is iiiiit?


Kevlar belts are far better than the steel ones. Ive only owned my Baja for a few months now and in that time i have totally fucking destroyed a fair amount of belts. Cheap chinese steel belts lasted me only 15km of hard off road use. Am getting hundreds of kms out of the Kevlar belts IF I don’t run them too tight. Belts should be just tight enough that they don’t skip under hard braking.


Ah, the empirical evidence I’ve been craving!

What was the failure mode of the belts? snapping?

Do you have any experience with glass fiber?

Much better.

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i’ve been using forever. Interestingly enough, the 280-5M-12 that i typically use doesn’t have any details about the contruction. And of course the image is wrong, its an HTD not the other one with the squared off teeth.

They last us about 6-8 months now.


I’ve got a set of conti belts been running now for 8 months charge a day and they are still going strong. Noticing some skipping now though when braking hard to a standstill. Teeth are fine but Brian says they don’t stretch so I won’t adjust the motors at all and trust his wise words.
@b264 I’m going to buy you a broom for all those sweeping statements mate.
What does a belt have to go through before it snaps Brian? What actually happens to it during the process?

i believe @b264 and I beleive in the process of elimination, so it must be your steel motor pulleys shrinking in the chill from all that wind speed.